20 On the Liehens near New-York. 



3. fastigiata Id. p. 297. Trunks. Apothecia terminal. 

 Frond thickening and fastigiate above. 



29. Collema. 



§ Frond leafy, lobes submembranaceous, loose, naked, 

 dark green. 



1. nigrescens. Id. p. 321. Trunks. Frond submonophyl- 



lous ; apothecia central, reddish brown. 



2. furvum. Id. p. 323. Ibid. Frond granulated on both 



sides ; apothecia scattered. 



§§ Frond leafy, very thin, subdiaphanous ; 

 apothecia sub pedicellate. 



3. tremelloides. Id. p. 326. Earth on moss and on rocks. 



Frond lead-colour, dotted ; apothecia scattered, of a 

 reddish brown, margin pale. 



4. lacerum. Id. p. 327. Trunks. Rare. Frond with small 



imbricated, laciniated, and fringed lobes. 



Order II. PELTATI. Apothecia peltate, without a border, 



fringed. 



30. CORNICULARIA. 



1. pubescens. Id. p. 302. On rocks and rotten wood near 



waterfalls. Rare. Frond short, blackish. 



2. jibrillosa. Id. p. 302. [sub var. pubescens.) Common on 



fences. Certainly a distinct species. 



31. UsNEA. 



1. Jlorida. Id. p. 304. Common on trunks and rocks. 



Frond erect, rigid, greenish gray, with horizontal fi- 

 bres; apothecia broad, with radiating cilia?. 



2. plicata. Id. p. 305. Branches of trees. Frond pendent, 



smooth, branches lax, much divided, and capillary. 

 var. (3. hirta. Ibid. Frond erect, somewhat rigid, 

 snbpulverulent, and roughish, branches much divided, 

 attenuated, and subfibrillose. 



